Score contribution per author:
α: calibrated so average coauthorship-adjusted count equals average raw count
As fundamental conditions and subject attributes in lab and field are very different, insights from existing meta-analyses performed on combined data from lab and field might imprecisely summarize the behavior in lab. Therefore, we focus on lab experiments to examine the influence of ‘earned versus unearned’ and ‘student versus charity recipient’ experimental protocols on donations using meta-analysis based on 80 dictator game studies spread over the time frame of 23 years (1997 – 2020). We also take advantage of more recent meta-analysis techniques to improve the robustness and offer methodological advancements for the examination of human behavior. We find that dictators on average share approximately 22% of their endowment. We also find robust evidence that earned endowment reduces benevolence when the recipient is a charity, while the use of charity instead of student as the recipient enhances benevolence with unearned endowment. These findings extend our understanding regarding the conditional effects of nature of endowment and recipient type on the behavior in lab.